The European hazelnut, Corylus avellana L., was imported into the U.S. in the late 1800's and is now grown throughout the Willamette Valley in Oregon. A native species of hazelnut, C. cornuta Marshall, is a common shrub found in forested areas of the Pacific Northwest. Foliage of both C. avellana...
Biology of Scaptomyza apicalis Hardy (Diptera: Drosophilidae) was studied in
relation to its host, meadowfoam, Limnanthes alba, a recent oil seed crop grown in the
Willamette Valley, Oregon. Populations of flies and larvae were monitored weekly over
three consecutive crop-years beginning in 1996. Yellow sticky traps gave relative
population estimates...
Barley yellow dwarf virus (BYDV) is a globally distributed pathogen of grasses that is transmitted by aphids. Little research has been done examining the response of aphids to different host grasses in naturally mixed communities. We measured the short-term fecundity of the aphid Rhopalosiphum padi, a widely distributed vector of...
Small remnants of 'natural' habitats exist today throughout much of the world. Upland prairies in the Willamette Valley, Oregon have been nearly eliminated by conversion to agriculture and other uses. As a result, very few prairies remain and at least four butterfly species that require this habitat appear to be...
Small broomrape, a holoparasitic weed, is a relatively new weed introduction in the Pacific Northwest that has contaminated a limited number of red clover fields in Oregon. Greenhouse and field studies were conducted to evaluate small broomrape response to common crop and weed species in the Pacific Northwest. Host species...
Douglas-fir, Pseudotsuga menziesii and white alder,
Alnus rhombifolia, species that are prevalent in the
Pacific Northwest, were fed to larvae of the gypsy moth,
Lymantria dispar L. Gypsy moth larvae from different
familial lines (egg masses) from a single geographic
population were evaluated on these hosts. The larvae
were fed...
The Pacific Northwest is an internationally important region for the production of Brassica seed and other seed crops including grass seed. Oregon lawmakers mandated research into the co-existence of canola (Brassica napus) with other Brassica production in the Willamette Valley and House Bill 2427 was signed into law in 2013,...